Have iOS use the same atomicops_internal implementation that Mac uses.

The atomicops_internal file for Mac and iOS is not actually architecture-specific, so it is being renamd to be arch-independent.

BUG=b/6754112
TEST=None

Review URL: https://chromiumcodereview.appspot.com/10696193

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@146584 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 197 insertions, 0 deletions

diff --git a/base/atomicops_internals_mac.h b/base/atomicops_internals_mac.h
new file mode 100644
index 0000000..658ed54
--- /dev/null
+++ b/base/atomicops_internals_mac.h
@@ -0,0 +1,197 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// This file is an internal atomic implementation, use base/atomicops.h instead.
+
+#ifndef BASE_ATOMICOPS_INTERNALS_MAC_H_
+#define BASE_ATOMICOPS_INTERNALS_MAC_H_
+
+#include <libkern/OSAtomic.h>
+
+namespace base {
+namespace subtle {
+
+inline Atomic32 NoBarrier_CompareAndSwap(volatile Atomic32 *ptr,
+                                         Atomic32 old_value,
+                                         Atomic32 new_value) {
+  Atomic32 prev_value;
+  do {
+    if (OSAtomicCompareAndSwap32(old_value, new_value,
+                                 const_cast<Atomic32*>(ptr))) {
+      return old_value;
+    }
+    prev_value = *ptr;
+  } while (prev_value == old_value);
+  return prev_value;
+}
+
+inline Atomic32 NoBarrier_AtomicExchange(volatile Atomic32 *ptr,
+                                         Atomic32 new_value) {
+  Atomic32 old_value;
+  do {
+    old_value = *ptr;
+  } while (!OSAtomicCompareAndSwap32(old_value, new_value,
+                                     const_cast<Atomic32*>(ptr)));
+  return old_value;
+}
+
+inline Atomic32 NoBarrier_AtomicIncrement(volatile Atomic32 *ptr,
+                                          Atomic32 increment) {
+  return OSAtomicAdd32(increment, const_cast<Atomic32*>(ptr));
+}
+
+inline Atomic32 Barrier_AtomicIncrement(volatile Atomic32 *ptr,
+                                          Atomic32 increment) {
+  return OSAtomicAdd32Barrier(increment, const_cast<Atomic32*>(ptr));
+}
+
+inline void MemoryBarrier() {
+  OSMemoryBarrier();
+}
+
+inline Atomic32 Acquire_CompareAndSwap(volatile Atomic32 *ptr,
+                                       Atomic32 old_value,
+                                       Atomic32 new_value) {
+  Atomic32 prev_value;
+  do {
+    if (OSAtomicCompareAndSwap32Barrier(old_value, new_value,
+                                        const_cast<Atomic32*>(ptr))) {
+      return old_value;
+    }
+    prev_value = *ptr;
+  } while (prev_value == old_value);
+  return prev_value;
+}
+
+inline Atomic32 Release_CompareAndSwap(volatile Atomic32 *ptr,
+                                       Atomic32 old_value,
+                                       Atomic32 new_value) {
+  return Acquire_CompareAndSwap(ptr, old_value, new_value);
+}
+
+inline void NoBarrier_Store(volatile Atomic32* ptr, Atomic32 value) {
+  *ptr = value;
+}
+
+inline void Acquire_Store(volatile Atomic32 *ptr, Atomic32 value) {
+  *ptr = value;
+  MemoryBarrier();
+}
+
+inline void Release_Store(volatile Atomic32 *ptr, Atomic32 value) {
+  MemoryBarrier();
+  *ptr = value;
+}
+
+inline Atomic32 NoBarrier_Load(volatile const Atomic32* ptr) {
+  return *ptr;
+}
+
+inline Atomic32 Acquire_Load(volatile const Atomic32 *ptr) {
+  Atomic32 value = *ptr;
+  MemoryBarrier();
+  return value;
+}
+
+inline Atomic32 Release_Load(volatile const Atomic32 *ptr) {
+  MemoryBarrier();
+  return *ptr;
+}
+
+#ifdef __LP64__
+
+// 64-bit implementation on 64-bit platform
+
+inline Atomic64 NoBarrier_CompareAndSwap(volatile Atomic64 *ptr,
+                                         Atomic64 old_value,
+                                         Atomic64 new_value) {
+  Atomic64 prev_value;
+  do {
+    if (OSAtomicCompareAndSwap64(old_value, new_value,
+                                 reinterpret_cast<volatile int64_t*>(ptr))) {
+      return old_value;
+    }
+    prev_value = *ptr;
+  } while (prev_value == old_value);
+  return prev_value;
+}
+
+inline Atomic64 NoBarrier_AtomicExchange(volatile Atomic64 *ptr,
+                                         Atomic64 new_value) {
+  Atomic64 old_value;
+  do {
+    old_value = *ptr;
+  } while (!OSAtomicCompareAndSwap64(old_value, new_value,
+                                     reinterpret_cast<volatile int64_t*>(ptr)));
+  return old_value;
+}
+
+inline Atomic64 NoBarrier_AtomicIncrement(volatile Atomic64 *ptr,
+                                          Atomic64 increment) {
+  return OSAtomicAdd64(increment, reinterpret_cast<volatile int64_t*>(ptr));
+}
+
+inline Atomic64 Barrier_AtomicIncrement(volatile Atomic64 *ptr,
+                                        Atomic64 increment) {
+  return OSAtomicAdd64Barrier(increment,
+                              reinterpret_cast<volatile int64_t*>(ptr));
+}
+
+inline Atomic64 Acquire_CompareAndSwap(volatile Atomic64 *ptr,
+                                       Atomic64 old_value,
+                                       Atomic64 new_value) {
+  Atomic64 prev_value;
+  do {
+    if (OSAtomicCompareAndSwap64Barrier(
+        old_value, new_value, reinterpret_cast<volatile int64_t*>(ptr))) {
+      return old_value;
+    }
+    prev_value = *ptr;
+  } while (prev_value == old_value);
+  return prev_value;
+}
+
+inline Atomic64 Release_CompareAndSwap(volatile Atomic64 *ptr,
+                                       Atomic64 old_value,
+                                       Atomic64 new_value) {
+  // The lib kern interface does not distinguish between
+  // Acquire and Release memory barriers; they are equivalent.
+  return Acquire_CompareAndSwap(ptr, old_value, new_value);
+}
+
+inline void NoBarrier_Store(volatile Atomic64* ptr, Atomic64 value) {
+  *ptr = value;
+}
+
+inline void Acquire_Store(volatile Atomic64 *ptr, Atomic64 value) {
+  *ptr = value;
+  MemoryBarrier();
+}
+
+inline void Release_Store(volatile Atomic64 *ptr, Atomic64 value) {
+  MemoryBarrier();
+  *ptr = value;
+}
+
+inline Atomic64 NoBarrier_Load(volatile const Atomic64* ptr) {
+  return *ptr;
+}
+
+inline Atomic64 Acquire_Load(volatile const Atomic64 *ptr) {
+  Atomic64 value = *ptr;
+  MemoryBarrier();
+  return value;
+}
+
+inline Atomic64 Release_Load(volatile const Atomic64 *ptr) {
+  MemoryBarrier();
+  return *ptr;
+}
+
+#endif  // defined(__LP64__)
+
+}   // namespace base::subtle
+}   // namespace base
+
+#endif  // BASE_ATOMICOPS_INTERNALS_MAC_H_